An artificial photosynthesis system was developed by researchers from the US Department of Energy (Lawrence Berkeley National Laboratory). The system can capture emissions of carbon dioxide before they reach the atmosphere and turn them into chemicals. The findings of the study were published in the journal Nano Letters.
The captures of carbon dioxide are transformed into useful products using solar energy. The system can produce pharmaceutical drugs, liquid fuels and biodegradable plastics. It is constructed with semiconducting nanowires and it uses bacteria which copies the process of natural photosynthesis. The system converts water and carbon dioxide into acetate, which is the most often met building block for biosynthesis.
This invention could solve the problem of carbon storage without involving environmental challenges. Various technologies which enable capturing carbon have been considered since fossil fuels such as coal are an important source of energy. This new system can provide a way of use the captured carbon dioxide in an effective way.
The bacterium used for the system was Sporomusa ovata, a type of bacterium which received electrons directly from the environment and uses this to decrease carbon dioxide. When the carbon dioxide is reduced to acetate by the S. ovata bacterium, the E.coli which are artificially engineered are used for chemical products.
Michelle Chang, a biosynthesis expert, declared:
“We were able to uniformly populate our nanowire array with S. ovata using buffered brackish water with trace vitamins as the only organic component.”
Chemist and co-author of the study Peidong Yang of Berkeley Lab’s Materials Sciences Division describes the system as a revolutionary leap forward in the domain of artificial photosynthesis. She added that the system could radically transform the chemical industry and the oil industry in the sense that fuels and chemicals could be produced in a completely renewable way instead of being extracted from the ground.
The technique used by the scientists uses a manmade forest consisting of silicon nanofibers and titanium oxide. Each tiny wire can work in a similar way with how chloroplast does. The S. ovate bacterium is placed at the base of each minuscule strand. When the wires are exposed to sun they generate electrons and electron holes which pass down to the bacteria. The bacterium is the one which synthesizes a biosynthetic intermediate and the electron holes divide water molecules and produce oxygen.
Besides solving the problem of turning the captured carbon into useful products, expert Chris Chang believes that this breakthrough is an example of how biology collaborates with material sciences.
Image Source: Photosynthesis for Kids